At what times should traffic controls be set up or taken down in a night traffic control zone?

The correct time to set up or take down traffic controls in a night traffic control zone is half an hour before sunset and half an hour after sunrise. This timing allows for adequate visibility for both the flaggers and the motorists, ensuring a safer environment as daylight diminishes and increases.

Setting up traffic controls too early or taking them down too late could confuse drivers or leave them without the necessary guidance when navigating through a work zone. By following the guideline of half an hour before sunset and half an hour after sunrise, it ensures that traffic control devices are in place during the critical periods when visibility is lower, thus enhancing safety for everyone involved.